NEW ORLEANS, LA - AUGUST 28: Lower Ninth Ward resident S.J. Thomas walks in front of the new levee wall along the Industrial Canal after assisting a neighbor prepare for Hurricane Isaac on August 28, 2012 in New Orleans, Louisiana. New Orleans is bracing for the approach of Hurricane Isaac, now a Category 1 storm, which is predicted to hit the city on August 29, the seventh anniversary of Hurricane Katrina. (Photo by Mario Tama/Getty Images)

New Orleans,US Gulf Coast Prepare For Approaching Isaac

<> on August 27, 2012 in New Orleans, Louisiana.

New Orleans,US Gulf Coast Prepare For Approaching Isaac

<> on August 27, 2012 in New Orleans, Louisiana.

New Orleans,US Gulf Coast Prepare For Approaching Isaac

<> on August 28, 2012 in New Orleans, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

LAPLACE, LA - AUGUST 29: Rescue workers transport residents trapped by rising water from Hurricane Isaac in the River Forest subdivision on August 29, 2012 in LaPlace, Louisiana. The large Level 1 hurricane slowly moved across southeast Louisiana, dumping huge amounts of rain and knocking out power to Louisianans in scattered parts of the state. (Photo by Chris Graythen/Getty Images)

Hurricane Isaac Hits New Orleans, Gulf Coast

LAPLACE, LA - AUGUST 29: Rescue workers transport residents trapped by rising water from Hurricane Isaac in the River Forest subdivision on August 29, 2012 in LaPlace, Louisiana. The large Level 1 hurricane slowly moved across southeast Louisiana, dumping huge amounts of rain and knocking out power to Louisianans in scattered parts of the state. (Photo by Chris Graythen/Getty Images)

Hurricane Isaac Hits New Orleans, Gulf Coast

<> on August 29, 2012 in New Orleans, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

<> on August 29, 2012 in New Orleans, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

OAKVILLE, LA - AUGUST 29: A tree blown over from Hurricane Isaac lies atop a cemetery tomb on August 29, 2012 in Oakville, in Plaquemines Parish, Louisiana. The parish, south of New Orleans, was the most heavily damaged by the hurricane. The system, which was downgraded to a tropical storm by the National Weather Service, moved slowly across the state, dumping large amounts of rain and knocking out power to half a million Louisianans. (Photo by John Moore/Getty Images)

Hurricane Isaac Hits New Orleans, Gulf Coast

<> on August 29, 2012 in New Orleans, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

<> on August 29, 2012 in New Orleans, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

<> on August 29, 2012 in New Orleans, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

NEW ORLEANS, LA - AUGUST 29: A tree is blown over outside Tulane Medical Center during rains from Hurricane Isaac on August 29, 2012 in New Orleans, Louisiana. The large Level 1 hurricane slowly moved across southeast Louisiana, dumping huge amounts of rain and knocking out power to Louisianans in scattered parts of the state. (Photo by Mario Tama/Getty Images)

Hurricane Isaac Hits New Orleans, Gulf Coast

<> on August 29, 2012 in New Orleans, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

OAKVILLE, LA - AUGUST 29: Rising waters from Hurricane Isaac flood a neighborhood on August 29, 2012 in Oakville, in Plaquemines Parish, Louisiana. The parish, south of New Orleans, was the most heavily damaged by the hurricane. The system, which was downgraded to a tropical storm by the National Weather Service, moved slowly across the state, dumping large amounts of rain and knocking out power to half a million Louisianans. (Photo by John Moore/Getty Images)

Hurricane Isaac Hits New Orleans, Gulf Coast

OAKVILLE, LA - AUGUST 29: Errol Ragas salvages blankets from his home as rising waters from Hurricane Isaac flood his neighborhood on August 29, 2012 in Oakville, in Plaquemines Parish, Louisiana. The parish, south of New Orleans, was the most heavily damaged by the hurricane. The system, which was downgraded to a tropical storm by the National Weather Service, moved slowly across the state, dumping large amounts of rain and knocking out power to half a million Louisianans. (Photo by John Moore/Getty Images)

Hurricane Isaac Hits New Orleans, Gulf Coast

<> on August 29, 2012 in Oakville, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

<> on August 29, 2012 in New Orleans, Louisiana.

Hurricane Isaac Hits New Orleans, Gulf Coast

OAKVILLE, LA - AUGUST 29: Errol Ragas walks past a cemetery to recover dry blankets from his home as rising waters from Hurricane Isaac flood his neighborhood on August 29, 2012 in Oakville, in Plaquemines Parish, Louisiana. The parish, south of New Orleans, was the most heavily damaged by the hurricane. The system, which was downgraded to a tropical storm by the National Weather Service, moved slowly across the state, dumping large amounts of rain and knocking out power to half a million Louisianans. (Photo by John Moore/Getty Images)